Ultimate Marvel vs Capcom 3 will be announced by Capcom at Comic-Con next week.

Capcom will release Ultimate Marvel vs Capcom 3 as a standalone game - similar to the release of Super Street Fighter IV - according to comic site The Quarter Bin. The new game is said to add 12 new fighters,
bringing the total character count to 50 (including DLC
characters Jill Valentine and Shuma-Gorath).

Characters including Marvel's Doctor Octopus and Capcom's Frank West and Strider Hiryu had previously been rumored as DLC characters for Marvel vs Capcom 3. The latter two characters even appeared in leaked screenshots that circulated online. Just as the current character roster is split evenly between Marvel and Capcom characters, it is presumed that the additional 12 fighters in Ultimate Marvel vs Capcom 3 will be evenly split as well.